Air brake



May 3l, 1932.

n AIR BRAKEA Filed Oct. 9, 1930 c, A. CAMPBELL HW .K 42V/ Gttorncgs Patented May 31, 1932 gUlwrrieo STATES PATENT GFF[CE-b` onAamzsy A. CAMPBELL, or wATEETowN, NEw YORK, AssreNoE rro THE NEW Yoaxf 1.

, AIE Emana coMrANY, yA coEroEnTroN kor NEw JERSEY AIE BRAKE ,c

Application led October 9, v1939.k Serial N'o. 487,617.

` This invention relates `to Vdeadman emergency valves.y The purpose'of the invention is to improvethe construction and "produce a device from which the working parts mayl be removed without the necessity ofbreaking any pipe joints.' 1 y The preferred embodiment ot the invention is illustrated in the accompanying drawings, in which,-'- 10 i Fig. 1 is a view, partly in plan and partly in section, on the line-11 of Fig. 2.

. Fig. -2 is a vertical axial section.

The device is supported in a body casting l 6.: This `is formed with a threaded connection 7 for the brakepipeya smaller threaded connection 8 for a control pipe, and a vent passage 9 whichy leads to atmosphere. The vent passage. 9 is shownthreaded, beause in some installations 'it is desired to attach a kvent'pipe leading to somey special point of discharge.

The body 6 is formed with a cylindrical chamber which is ,conveniently coaxial with the vent passage 9, and which, at the opposite end is open and threaded, as indicated'at 11, to receive a removable closure'cap 12.' vThis closure capis lformed with 5a hexagonal hollow boss 13 to receive iaV wrench, by means of the body 6 when the cap-12 is removed, is a unitary structure comprising a cylinder bushing 18, a valve seat member 19 and connecting arms 21 which form a spider. The

- valve seat member 19 is provided with an annular shoulder 22 which seats on the gasket 17. The lower end of the cylinder bushing 18 forms a shoulder 23 which surrounds the upper ends of the arms 21 and which seats on the gasket 15. The threaded boss of the cap 12 seats on the upper end of the cylinder bushing 18' and forces this downward, simultaneously compressing bothv of the gaskets 15,

and17.y The body is counterbored to provide per portion of the bushing, and thisis notched, as indicated at`25, to provide a.l passage from 'the interior ofthe bushing tothe ycontrolling pipe connection 8.

ian annular chamber 24 surrounding the up n Slidably mounted in and guided by the Y bushing 18 is a skirted piston 26 having one sealing ring 27. The ring 27 is an ordinary snap ring. Formed integral with the piston 28 is a valve bodyw29. This has a rubber or other suitable seating face 31 which coactsrk with the valve seat 19. To assist in guiding the valve and 'to conline the gasketv 31, there isprovided Ia winged pilot 32 formedl in tegrally with the stem 33. "The stem 33 veX-Y tends through the valve body 29 and the re- 26'and connected thereto by a reduced neck c duced neck 28,y into the space above the piston 26 where :it receivesa nut 34. The nut holds ythe parts in `assembled relatOD.

4The parts 18 to V23and 25 to 34 make 'upa valve land motor v unit which is inse'rtiblev through the open side of the body 6.

Thecap 12 carriesa downwardly extends ing annular stop"member 35 which coacts withfthe nutf34 and serves to limt'the up-` wardV motion ,of kthe *pistony andvalve. A

.spring 36 surrounding the boss 35, reacts between the vcap 12 *and thepiston 26 and urges the piston 26 and valve 29 in a downward (valve closing) direction.y A minute equalizing port 37 connectsthespacesabove and belowthe piston v26. The space below ythe piston 26.and immediately above the valve 29is in free communication withV the lbrake vpipe yconnection 7.

In the construction shown in the drawings,

a removable strainer is interposed. To that yend the `'body 6 ,is `formed witha partition 38, U-shaped in plan (see Fig. 1), and formed vat onejside with a conicalseat aperture 39,4 and on the other side With a circularfaper Yture 41. A vcylindrical gauze strainer 42 is inserted l through' the second aperture, yand seats at its end against the conical portion of the first aperture. This strainer is removable, and is inserted throughfa threaded aperjao relay ventv valve.

that brake pipe air flows through the strainer.

42 to the space below the piston 26, then fiows through the port 37 to the space above this piston, until the pressures above and below the piston equalize. Under suchfconditions the spring 36 maintains the valve 29 inV its seated or closed position. If the connection 8 be vented to atmosphere, the port 87 is inadequate to maintain the equalization of pressure, and the preponderating pressure, acting) on the lower side off the piston 26, forces this upward against the resistance of the spring 36, and vents the brake pipe directly to atmosphere through the passage 9.

Relay vent valvesr having4 thisoperative characteristic are well known and are cus` rtomarily used with what are known as` deadmans valves. These valves have a normal opening tendency, and must be held closed by the operator. Some types are associated with controller handles; others with brake valve handiles, and still, others are of the foot-opervaterltypeh requiring` the opera-tor to keep. his

foot onthe valve. The idea underlying all of these mechanisms is to'insure attention by the operator and that he remain continuously at his post.k Should heI release lthe valve, either through inattention, or because ofl illness, the valve will open and vent the space above` the piston 26, thus causing the ventk valve 29rv to open.

As heretofore constructed the failure of any working part of the relay-valve, required the dismounting of the entire valve body, and the breaking of atleast two pipe joints The present construction permits the withdrawal of the working parts of the valve and the substitution,y of new parts while the valve body remainsconnected. rlhus, unless the f valve body itself be damaged, repairscan be made without breaking any pipe joints. The removable strainer in conjunction with a device of this sort, greatly simplifies maintenance. y

While I` have illustratedfthe best form of thedevice known to me, the inventive concept ing a cylinder and valve seat rigidly connected together and a piston and valve rigidly connected together, the piston working in said cylinder and the valve coacting with said seat; gasket means for sealing said cylinder Vand seat to `said body, in coactive relation -and seat to said body, in coactivc relation with parts therein; and a kremezrvable closure: for said open side threaded to said body and serving to force said cylinder and seat against said gasket means.

3. In a deadman emergency vent valve,

the combination of a body having a control pipe connection, abrake pipe connection, anda vent passage communicatingthrough the bodywith said brake pipeconnection. said body being formed with oneopen side;

a bushing structure removably mounted inf said body, insertible through said open side and including a cylinder bushing, a valve seat registeringfwith said vent passage and a connecting spider, the cylinder bushing being ported;A adjacent its end to afford commlmication from the interior of said bushing tosaid control pipe connection; gasket. means for sealing said ,cylinder bushing and said` valve seat to said body; a cap removably mounted on said body to'close said open side and seat' said bushing structure against saidr gasket means; a ported piston slidably mounted in said cylinder bushing; a. valve carried by said piston and adapted to closeagainst'said seat; and a spring urging said valve in a. seating direction.

In testimony whereof I4 have signed my name to this specification.'

CHARLES A. CAMPBELL. 

